diff -uNr i3status-2.12/src/print_disk_info.c i3status-2.12.mod/src/print_disk_info.c
--- i3status-2.12/src/print_disk_info.c	2018-05-11 12:10:46.000000000 +0300
+++ i3status-2.12.mod/src/print_disk_info.c	2018-06-21 19:33:34.403580664 +0300
@@ -144,7 +144,7 @@
         char *sanitized = sstrdup(path);
         if (strlen(sanitized) > 1 && sanitized[strlen(sanitized) - 1] == '/')
             sanitized[strlen(sanitized) - 1] = '\0';
-        FILE *mntentfile = setmntent("/etc/mtab", "r");
+        FILE *mntentfile = setmntent("/proc/self/mounts", "r");
         struct mntent *m;
 
         while ((m = getmntent(mntentfile)) != NULL) {